Disc for Disc Golf

Abstract

A disc for disc golf, the disc including a central plate portion and a rim surrounding said central plate portion and extending from the plate portion in an axial direction of the disc. The central plate portion includes a core of a first polymer-based material, and, at least in the region of the rim, there is provided a second polymer-based material, which is chemically bonded to the first polymer-based material and which forms an outer surface of the disc. The first polymer-based material has a higher tensile strength than the second polymer-based material, and the second polymer-based material is softer than the first polymer-based material. The first polymer-based material forms a core of the rim and the second polymer-based material forms a coating on top of the first polymer-based material and encloses the core of the rim.

Claims

1. A disc for disc golf, comprising a central plate portion and a rim surrounding the central plate portion (1) and extending from the plate portion (1) in an axial direction of the disc, wherein: the central plate portion comprises a core (3) of a first polymer-based material, at least in the region of the rim, there is provided a second polymer-based material, which is chemically bonded to the first polymer-based material and which forms an outer surface of the disc, the first polymer-based material has a higher tensile strength than the second polymer-based material, the second polymer-based material is softer than the first polymer-based material, and the first polymer-based material forms a core of the rim and the second polymer-based material forms a coating on top of the first polymer-based material and encloses the core of the rim.

2. The disc according to claim 1, wherein a thickness of the coating of the second polymer-based material that encloses the core of the rim is 1.0-7.0 mm.

3. The disc according to claim 1, wherein the thickness of the coating of the second polymer-based material that encloses the core of the rim is 0.005-1.0 mm.

4. A disc according to claim 1, wherein the first material has a tensile strength which is at least 5 MPa higher than a tensile strength of the second material.

5. The disc according to claim 4, wherein the tensile strength of the first material is at least 10 MPa higher than the tensile strength of the second material,

6. The disc according to claim 4, wherein the tensile strength of the first material is above 15 MPa.

7. The disc according to claim 1, wherein the second material has a hardness which is below 50 Shore D.

8. The disc according to claim 1, wherein the first material has a hardness which is above 30 Shore D.

9. The disc according to claim 1, wherein the central plate portion is generally circular and has a radius r, and wherein, at least on the side of central plate portion from which the rim extends in the axial direction, a coating of the second material covers the core of the central plate portion from the rim and at least 0.25 r towards a center of the disc.

10. The disc according to claim 9, wherein, at least on the side of central plate portion from which the rim extends in the axial direction, the coating of the second material covers the core of the central plate portion from the rim and at least 0.75 r towards the center of the disc.

11. The disc according to claim 1, wherein the central plate portion is generally circular and has a radius r, and wherein, on a side of the central plate portion which is opposite to the side of the central plate portion from which the rim extends in the axial direction, a coating of the second material covers the core of the central plate portion from the rim and at least 0.25 r towards a center of the disc.

12. The disc according to claim 11, wherein, on a side of the central plate portion which is opposite to the side of the central plate portion from which the rim extends in the axial direction, the coating of the second material covers the core of the central plate portion from the rim and at least 0.75 r towards the center of the disc.

13. The disc according to claim 1, wherein the second material forms a coating which covers and encloses at least 95% of the outer surface area of a core formed by the first material.

14. The disc according to claim 1, wherein the first material comprises any of a thermoplastic urethane or a thermoplastic elastomer material.

15. The disc according to 1, wherein the second material comprises any of a thermoplastic urethane or a thermoplastic elastomer material.

16. The disc according to claim 14, wherein the thermoplastic elastomer material comprises any one from the group consisting of thermoplastic olefins, thermoplastic block copolymers, thermoplastic vulcanized polypropylene-EPDM-mixtures, thermoplastic polyester mixtures, Copolyester, thermoplastic urethanes thermoplastic polyamides.

17. The disc according to claim 1, wherein the disc has a diameter in the range of 20-23 cm, the central plate portion has a thickness in the range of 1.5-3.0 mm, the rim has a maximum thickness of 0.5-3.0 cm in the radial direction of the disc and a height in the axial direction of the disc in the range of 1.0-3.0 cm.

18. The disc according to claim 17, wherein the second polymer-based material is provided as a coating on the first polymer-based material and has a thickness in the range of 0.05-1.0 mm in the region of the central plate portion and a thickness of 1.0-7.0 mm in the region of the rim.

19. The disc according to claim 1, wherein the coating has a thickness in the range of 0.05-1.0 mm in the region of a central part of the central plate portion, a thickness of 0.01 mm in a region adjacent to the rim, and a thickness in the range of 0.005-0.01 mm in the region where the coating encloses the core of the rim.

20. The disc according to claim 15, wherein the thermoplastic elastomer material comprises any one from the group consisting of thermoplastic olefins thermoplastic block copolymers, thermoplastic vulcanized polypropylene-EPDM-mixtures, thermoplastic polyester mixtures, Copolyester, thermoplastic urethanes thermoplastic polyamides.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] An embodiment of a disc according to the present invention will be presented more in detail with reference to the enclosed drawing, on which

[0031] FIG. 1 is cross-section of a disc according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0032] FIG. 1 shows a schematic representation of a cross-section of a disc for disc golf according to the present invention. The disc comprises a central plate portion 1 and a rim 2 surrounding the central plate portion 1. The central plate portion 1 has a certain curvature but extends mainly in a plane which is parallel with a radius of the central plate portion 1, defining a radial direction x. The central plate portion 1 is circular. The rim 2 extends from the central plate portion 2 in an axial direction y of the disc, perpendicular to the radial direction x.

[0033] The central plate portion 1 as well as the rim comprises a continuous core 3 of a first polymer-based material, and a coating 4 of a second polymer-based material, which is chemically bonded to the first polymer-based material and which forms an outer surface of the disc. In the embodiment presented here, the first polymer-based material consists of thermoplastic urethane, TPU, having a hardness of 50 Shore D and a tensile strength of 50 MPa. The second polymer consists of a thermoplastic block copolymer (TPE-S) having a hardness of 40 Shore D and a tensile strength of 40 MPa. Measurement of tensile strength is made according to standard ASTM D412, while measurement of the hardness is made according to ASTM D2240.

[0034] The chemical bonding between the first polymer material and the second polymer material is the result of an injection moulding process in which the two materials are injected almost simultaneously in a mould and permitted to solidify together in said mould.

[0035] The coating 4 which covers and encloses at least 95% of the outer surface area of the core 3 formed by the first material. Only in the region of where the polymers have been injected into the mould is there a very small area where there is no coverage. This area may be almost negligible compared to the total outer surface of the disc.

[0036] According to one embodiment, the disc has a diameter of 211 mm, the central plate portion has a thickness of 2.0 mm in a central region thereof, increasing up to 3 mm in adjacent to the rim (as a result of the coating 4 growing thicker towards the rim 2). The core 3 in the central plate portion 1 has a thickness of 1.8 mm. The rim has a maximum thickness of 10.0 mm in the radial direction x of the disc and a height of approximately 20 mm the axial direction y of the disc.

[0037] According to one embodiment, the coating 4 has a thickness in the range of 0.1 mm in the region of a central part of the central plate portion 1, increasing to a thickness of 1.0 mm in a region adjacent to the rim, and a thickness in the range of 1.0-4.1 mm in the region of the rim 2 (thinner towards the central plate portion 1 and on an inside of the disc). In the rim 2, the core 3 has a maximum thickness in the radial direction x of 5.5 mm.

[0038] According to an alternative embodiment, the coating 4 has a thickness in the range of 0.1 mm in the region of a central part of the central plate portion 1, decreasing to a thickness of 0.01 mm in a region adjacent to the rim, and a thickness in the range of 0.01 mm in the region where it encloses the core 3 of the rim 2.